Edward



NO. 111,254. PATENIE'D JAN. 24, 1871. E; s; RITCHIE. CARD FOR MARINERS LIQUID OOMPASSBS.

EDWARD RITCHIE, or BROOKLINE, MASSAGHUSETTS.

Letters Patent No. 111,254, dated January 24, 1871.

iMPROVEMENT m CARDS roe MARrnERs'u um-eoMPAssEs.

The Schefluleref ned to in these Letters Fatent and making paxt' of the name.

To all persons to whom these presents away come Be it known that I, EDWARD S Rrrcnm, of Brookline, in the county of Norfolk and State of Massachusetts, have made a new and useful invention having reference to the Cards of Mariners" Compasses; and do hereby declare the same to-be fully described in the following specification and represented in the accompanying drawing, of whieh- Figure 1 denotes a top view, and

Figure 2, a transverse section of a compass-card as made in'my improved manner. h

The common method heretofore practiced for making the cards'ot' the mariuers compass has'been by pasting upon a'disk of mica a sheet of paper having the cardinal divisions made or fixed on it.

Such cards, however-,would not-be used in the bowls of what are termed liquid -compasses, such bowls being filled with water or a mixture of such and alcohol, for the liquid will dissolve the paste or cementand loosen the paper from the mica. i I

In consequence of this, it has been necessary to make the cards of porcelain, metal, or mica, with the divisions and lettering painted on them.

On May 12, 1868, a patent was granted to me for a paint for, or a mode of, painting such cards by iheuse of' albumen or casein mixed with one or more pigments, and rendered insoluble by coagulation.

I have since discovered that'the pigment or pigments may be dispensed with, and the albumen or other like coagulative substance 'may be used alone and coagulated, such enabling me to make of paper or cloth, or other like absorbent material, a compasscard, either in whole or in part, for use in a compassbo'wl containing a liquid.

Therefore, in carrying out my present invention, I protect the card, when of paper or 'an absorbent material, by covering or saturating with albumen or a like coagulative substance the part or parts to be In this case the outer coagulative covering may beof the coagulative material alone, or of such in mix ture with one or more pigments.

Generally, in carryiug'out my present invention, I cement, by means of albumen or an equivalent coagulative material, the stratunii or backinga, (see fig. 2,) of union or thin metal, to the stratum b, of paper, cloth, or other material bearing the cardinal divisions, (the cement being shown at e in the drawing,) and'snbsequently, or in the meantime,l coagulate the albumen by heat or by plunging the card into alcohol, or by any other chemical means-whereby the albumen may be'rendered insoluble in the liquid used in the compass-bowl.

A stratum" of paper or cloth, as shown at 6, may'also be applied t-o'the back of the backing of mica and be cemented thereto by albumen coagulated, as set forth.

Generally, in making'the card, I prefer to apply to the mica a stratum of thin cloth, covering both sides and the outer (and if the card has an open middle portion the inner) edges by means of albumen, and afterward\covering the upper surface with a composition of albumen and a pigment and eiiect coagula tion, and subsequently have the divisions printed upon it.

By thislmeans there will be prevented any distortion of the divisions, such as might result by shrinking or stretching of the paper or cloth, provided the divisions were applied to it before its fixation to the mica.

In consequence-of the elasticity of the paper or cloth, and the'st-ronger adhesion of the paint or albuminous covering upon it than upon a metal surface, the divisions of the card may readily be printed or lithographed upon the card, which it has not been found practicable to do when the card was made of metalor mica, painted with a composition of albumen and a pigment.

. I claim-- 1. A marinefls compass-card, as composed of a sheet of paper, cloth, or other proper material, protected by albumen or other coagulative substitute alone, coagulated, as described.

2. A marine-ifs liquid compass-card, as composed of two or more strata cemented together by albumen or other like coagulativc substance, coagulated, as set forth.

3. A mariners liquid compass-card, as composed oi; p,. 

